Subject: Re: bug#70707: 30.0.50; [PATCH] ; Check the process param in function (python-shell-completion-at-point)

From: kobarity <[email-masked]>
Date: Tue, 07 May 2024 00:12:10 +0900

Lin Sun wrote:
> 
> > Hi,
> >
> > There is an unexpected error message happening with function
> > `python-shell-completion-at-point`.
> > > Wrong type argument: processp, nil
> > It happened because the function does NOT check the process param.
> > The patch will check the param and display a user error message gracefully.
> >
> > Steps to reproduce the issue.
> > 1. $ emacs -q /tmp/a.py # start emacs and open a python source file
> > 2. type "C-c C-p" (or M-x run-python) to start a python shell
> > 3. type exit() to stop the python process but the buffer still exists
> > 4. Switch to *python* buffer, then M-x
> > python-shell-completion-at-point  will get the error message
> >
> > Please help review the patch. Thanks. Regards
> >
> >
> > From aa44c95c7f13f2d68be83260e618cf4d806b313b Mon Sep 17 00:00:00 2001
> > From: Lin Sun <[email-masked]>
> > Date: Wed, 1 May 2024 06:55:31 +0000
> > Subject: [PATCH] ; Check the process param in function
> >  (python-shell-completion-at-point)
> >
> > * lisp/progmodes/python.el (python-shell-completion-at-point):
> >   Check the process param at the beginning of the function.
> > ---
> >  lisp/progmodes/python.el | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
> > index d6c29e5ffc..4b2e2f8215 100644
> > --- a/lisp/progmodes/python.el
> > +++ b/lisp/progmodes/python.el
> > @@ -4708,6 +4708,8 @@ python-shell-completion-at-point
> >  Optional argument PROCESS forces completions to be retrieved
> >  using that one instead of current buffer's process."
> >    (setq process (or process (get-buffer-process (current-buffer))))
> > +  (unless process
> > +    (user-error "No active python inferior process"))
> >    (let* ((is-shell-buffer (derived-mode-p 'inferior-python-mode))
> >           (line-start (if is-shell-buffer
> >                           ;; Working on a shell buffer: use prompt end.
> > --
> > 2.20.5
> 
> Hi Kobarity, Please help review the patch for checking process and
> emitting user-error when it's not available. Thanks.

Hi Lin,

The patch itself looks good to me.

> > 4. Switch to *python* buffer, then M-x
> > python-shell-completion-at-point  will get the error message

As `python-shell-completion-at-point' is not an interactive function,
I tested with M-x complete-symbol.